Oil supply means for tanks containing blended fuel and oil

ABSTRACT

A vehicle which uses &#34;blended&#34; fuel, i.e., fuel and lubricating oil combined, is provided with a fuel tank and an oil tank. A measuring device receives a predetermined amount of oil, and when an actuation occurs, usually associated with a fuel-filling operation the measured amount of oil is discharged into the fuel tank where it blends with the fuel. The actuation may, for example, be derived from the opening and/or closing of a fuel tank closure, or from the insertion of a fuel filler nozzle into the tank.

This is a division of application Ser. No. 31,383, filed Apr. 19, 1979,now U.S. Pat. No. 4,262,710.

This invention relates to an oil-blended fuel tank for use with anengine using the so-called "blended fuel", in which a fuel (for example,gasoline) and a lubricating engine oil are blended. It contemplates toprovide a fuel tank with a measuring device for automatically and easilyadding a correct amount of lubricating oil to the fuel in the full tank.

As is well known in the relevant art, a two-cycle engine generally usesan oil-blended fuel. This blended fuel is sold at so few gas stationsthat a user of the engine is frequently required separately to purchasethe fuel and lubricating oil and to blend them himself. However, theuser is liable to dislike the blending operation because this operationoften causes his hands and clothing to be soiled by the oil. With thisin mind, there has been developed the so-called "separate oil supplysystem", in which a fuel tank and an oil tank are installed separatelyon a vehicle so that the lubricating oil may be supplied to the engineby means of an oil pump which is provided separately from fuel supplymeans (the carburetor). However, this system involves the complicationof the separate oil pump.

It is therefore an object of the present invention to eliminate theafore-mentioned drawback and to provide a fuel tank with an oil supplymeans (sometimes called an "oil blender"), in which the desiredoil-blended fuel can be prepared automatically in response to the fuelsupplying operation such as the opening and closing operations of thefiller cap, without requiring complex devices such as an oil pump, whilestill eliminating the previous blending operation of the fuel and oil.

An oil supply system according to this invention includes a fuel tank,an oil tank, and a measuring device. The measuring device receives apredetermined quantity of oil from the oil tank, and discharges it intothe fuel tank where the oil blends with the fuel to form the blendedfuel. Actuation means actuates the measuring device to release thepredetermined amount of oil.

According to a preferred but optional feature of the invention, theactuation means includes the cover of the fill port of the fuel tank.

According to another preferred but optional feature of the invention,the actuation means is responsive to insertion of a fuel nozzle into thetank.

According to yet other preferred but optional features, the measuringdevice is a receptacle of known volume with a separately valved oilinlet and oil outlet, or a piston-cylinder assembly with known bore andstroke.

The above and other features of this invention will be fully understoodfrom the following detailed description and the accompanying drawings,in which:

FIG. 1 is a side elevation of a motorized bicycle which includes theinvention;

FIG. 2 is a cross-section taken at line 2--2 in FIG. 1 showing thepresently preferred embodiment of the invention;

FIG. 3 is a top view of a portion of FIG. 2;

FIG. 4 is a view taken at line 2--2 in FIG. 1, but showing anotherembodiment of the invention; and

FIGS. 5 and 6 are views taken at line 2--2 in FIG. 1, showing stillanother embodiment of the invention in its repose and actuatedconditions, respectively.

Reference numeral 1 appearing in FIG. 1 indicates the frame of thebicycle, numeral 2 a front wheel, numeral 3 a rear wheel, numeral 4 ahandlebar, numeral 5 a pedal for driving the rear wheel 3, and numeral 6an engine of the two-cycle type equipped with a carburetor 6a. Engine 6is adapted to turn a centrifugal clutch 8 through a driving belt 7. Adriving roller 9 is connected to the centrifugal clutch 8 and is broughtinto and out of operational contact with the rear wheel 3 so that wheel3 may be driven by the frictional contact between itself and drivingroller 9, or disconnected therefrom. Indicated at reference numeral 10is a luggage carrier, to the lower side of which is mounted a fuel tank11 (sometimes called an "oil blended fuel tank") for supplyingoil-blended fuel to the intake passage of engine 6. A lubricating oiltank 12 is mounted on the upper side of the luggage carrier 10. Theoil-blended fuel supplied to the engine intake passage is supplied tothe engine 6 after it is metered and mixed with intake air by carburetor6a, as is well known in the art.

The details of tanks 11 and 12 will now be described with reference toFIGS. 2 and 3. The oil-blended fuel tank 11 has through its bottom walla fuel supply outlet 13 leading to engine 6. Its side wall is equippedwith a fuel level gauge 14 which is made of a transparent tube (or pipe)that provides communication between the upper and lower portions of fueltank 11. The top wall of tank 11 is pierced by a connecting port 15 anda fuel (or gasoline) supply port 16.

The threaded lower end of a connector 17 is screwed into the connectingport 15. Connector 17 has a cup-shape, and has a lower valve port 18which communicates with fuel tank 11 by way of connecting port 15. Theinside space of the connector 17 forms a communication passage betweenthe lubricating oil tank 12 and fuel tank 11.

In this embodiment, the communication passage also acts as a meteringchamber 19 for metering lubricating oil which is to be blended into thefuel. A sealing member 20 is screwed into the upper portion of theconnector 17. Into sealing member 20 there is removably screwed anoutlet portion 21 which is formed in the bottom wall of the oil tank 12.The sealing member 20 thus far described is formed with an upper valveport 22 which is made co-extensive and aligned with the afore-mentionedlower valve port 18, and which has communication with the oil tank 12 byway of the opening of the outlet portion 21. On the other hand, there isaccommodated in the metering chamber 19 a valve member 23 which isformed with upper and lower valve stems 24a and 24b extending therefromuntil they fit in upper and lower stem guides 25 and 26, respectively,while freely extending through the upper and lower valve ports 22 and18. The valve member 23 is sized and shaped to have its lower sideseated removably upon the lower valve port 18 thereby to shut off thevalve port 18 but to open the upper valve port 22 at the same time.Likewise, the upper side of the valve member 23 can be removably seatedupon the upper valve port 22 to shut off the same while opening thelower valve port 18. The valve member 23 thus constructed is alwaysurged downwardly by the biasing action of a coil spring 27.

An oil level gauge 28 made of a transparent tube or the like iscommunicated at its lower end with the metering chamber 19. This levelgauge 38 extends upwardly along the side wall of the oil tank 12 untilits upper extremity is vented to the atmosphere. Here, referencenumerals 29, 30 and 31 indicate an oil supply port opened in the topwall of the oil tank 12, an oil cap for closing the oil supply port 29,and a sealing member, respectively.

There is provided in the afore-mentioned fuel tank 11 a bracket 32 whichdepends from the top wall of the tank 11 and to which an operating lever34 is hinged by means of a pivot pin 33. The operating lever 34 thusconstructed has its intermediate portion abutting against theafore-mentioned lower valve stem 24b, which depends from the valvemember 23, and its leading free end extending up to a position below thefuel supply port 16. There is interposed between the leading end portionof the operating lever 34 and the fuel tank 11 a coil spring 35 whichhas a higher elastic force than the afore-mentioned coil spring 27 sothat the operating lever 34 is always urged upward or counter-clockwiseabout the pivot pin 33 by the biasing force of the coil spring 35 whileovercoming the biasing force of the coil spring 27.

On the other hand, the fuel supply port 16 of the fuel tank 11 can beopened and closed by means of a fuel cover 36, which is composed of afuel cap 37 screwed onto the outer wall of the port 16 and a closingmember 38 covered by the cap 37. The closing member 38 thus constructedis formed on its circumference with a pair of opposed engagement members39, which can be guided in a pair of axial guide grooves 40 formed inthe wall of the fuel supply port 16, when the closing member 38 is to befastened, until they are retained in a pair of circumferential retaininggrooes 41 merging into the guide grooves 40. In order to fasten theclosing member 38 to the fuel support port 16, more specifically theengagement members 39 thereof are fitted and forced into the guidegrooves 40, and the members 39 are then turned in one direction untilthey are brought into engagement with the retaining grooves 41.Reference numerals 42, 43 and 44 indicate a sealing member, an airbreather formed in the closing member 38, and another air breatherformed in the fuel cap 37, respectively. Closing member 38 is madeintegral with a push rod 45, which depends therefrom until its lowerextremity abuts against the leading end portion of the afore-mentionedoperating lever 34. As a result, this operating lever 34 can be turnedthrough the push rod 45 by fastening and removing the closing member toand from the fuel supply port 16.

The operations of the above embodiment of FIG. 2 is as follows. In casethe fuel supply port 16 is shut by the fuel cover 36 of the fuel tank11, i.e., by means of the closing member 38 and the fuel cap 37 underthe condition in which the oil tank 12 is filled up with sufficientlubricating engine oil, then the push rod 45 depending from the closingmember 38 pushes down the leading end of the operating lever 34. As aresult, the valve member 23 is pushed down by the biasing force of thecoil spring 27 so that its lower side is seated to shut off the lowervalve port 18 while opening the upper valve port 22 at the same time. Asa result, the inside space of the oil tank 12 communicates with meteringchamber 19 via the opening of the outlet portion 21 and the upper valveport 22 so that the engine oil flows from the oil tank 12 downwardlyinto the metering chamber 19 to its full predetermined capacity.

When the fuel tank is to be refilled as the consequence of consumptionof the oil blended fuel in the fuel tank 11, the fuel supply port 16 ofthe tank 11 is opened. More specifically, when the cap 37 is loosened toremove the closing member 38, the push rod 45 leaves the operating lever34 together with the closing member 38 so that the operating lever 34 isturned upward, i.e., counter-clockwise by the biasing force of the coilspring 35. As a result, the valve member 23 is raised by the lower valvestem 24b against the biasing force of the coil spring 27 so that thelower side of the valve member 23 is unseated to open the lower valveport 18 and the upper side of the same is seated upon the upper valveport 22 thereby to shut off the port 22. Then, the oil contained inmetering chamber 19 flows down into the fuel tank 11 via the lower valveport 18 and the connecting port 15. Under this particular condition, itshould be noted that since the upper valve port 22 is shut off by meansof valve member 23 lubricating oil in tank 12 cannot flow down into fueltank 11. Thus, only the predetermined quantity of which occupied themetering chamber 19 will be supplied to the fuel tank 11. Since,moreover, the oil level gauge 28 having communication with the meteringchamber 19 has its upper end vented to the atmosphere, the oil in themetering chamber 19 can flow swiftly and smoothly into the fuel tank 11.With the fuel supply port 16 opened, meanwhile, only fuel is supplied tothe fuel tank 11 via the open port 16. Then, the fuel flowing into thetank 11 establishes therein such vortexes as can stir and blend the oilwhich has already been supplied. In these ways, it is possible toreserve in the fuel tank a fuel into which a preset proper quantity ofoil is blended.

When the fuel tank 11 is filled up with the oil-blended fuel, the fuelsupply port 16 is closed. In this embodiment, when the closing member 38is fastened, the push rod 45 pushes against the operating lever 34 inthe downward direction, against the biasing force of the coil spring 35.As a result, valve member 23 is moved down by coil spring 27 to open theupper valve port 22 and to close the lower valve port 18. Then, oilflows down from the oil tank 12 into the metering chamber 19, thuspreparing the next amount of oil to be supplied to fuel tank 11. Afterthe closing member 38 is retained, the fuel cap 37 is screwed down.

According to the embodiment thus far described, a preset quantity ofengine oil can be automatically supplied to the fuel tank 11 by theremoval of the fuel cover 36 from the tank 11, which forms one step ofthe fuel supplying process. As a result, it is sufficient merely to pourthe fuel into the supply port 16 without making unnecessary tediousoperations, as has been required in the prior art to blend in advancethe oil and the fuel outside of the fuel tank. Since, moreover, theembodiment makes use of gravity, its construction and handling areconsiderably simplified in comparison with the prior art that resorts toa special pump.

Oil tank 12 is made removable from the sealing member 20 of theconnector 17 forming the metering chamber 19. Therefore, if the oil tank12 is emptied, it can be replaced by a new tank filled up with theengine oil although the oil could instead be poured into the supply port29 by removing the oil cap 30.

In the embodiment of FIG. 4, there is connecting tube 50 (which mayalternatively be a pipe) connected to the bottom of the lubricating oiltank 12. It forms a communication passage 51 which in turn is connectedto a metering chamber 52 formed in the oil-blended fuel tank 11. Themetering chamber 52 has its upper extremity defined by a piston 54 whichis fitted vertically movably in a cylinder 53. The metering chamber 52thus defined has communication both with the communication passage 51 byway of a plurality of inlet ports 55 which are formed in the side wallsof cylinder 53, and with the inside of the fuel tank 11 by way of aplurality of outlet ports 56 which are formed in the side wall of thecylinder. There is mounted around the inlet ports 55 an inlet checkvalve 57 which allows the oil to flow only in the direction from thecommunication passage 51 to the metering chamber 52. There is alsomounted around the outlet ports 56 an outlet check valve 58 which allowsthe oil to flow only in the direction from the metering chamber 52 tothe fuel tank 11.

A coil spring 59 is mounted in the metering chamber which is operativeto urge the piston 54 upwardly at all times. In FIG. 4, the top wall ofthe piston 54 is shown with its upper surface abutting against the lowerend of push rod 61 which depends from a fuel cover 60 removably coveringthe oil supply port 16. This establishes the lowermost position of thepiston. Reference numeral 62 indicates a stopper for regulating theuppermost position of the piston 54.

In FIG. 4, when fuel cover 60 is removed, the push rod 61 is extractedwith it, so that piston 54 is raised by the biasing force of coil spring59. As a result, metering chamber 52 is "evacuated" (enlarged) so thatthe lubricating oil is sucked from the oil tank 12 into the meteringchamber 52 by way of the communication passage 51 and the inlet ports55. The piston raises to its dashed-line position in FIG. 4, so as todraw in a known, predetermined quantity of oil. After the fuel issupplied through the open fuel supply port 16, supply port 16 is shut byreattaching means fuel cover 60. Then the push rod 61 pushes down thepiston 54 against the biasing force of the coil spring 59 so that thepressure in the metering chamber 52 is boosted to pump out the oil fromthe metering chamber 52 into the fuel tank 11 by way of the outlet ports56, and the piston is retained at its position illustrated in solidline. As a result, the engine oil is blended into the supplied fuel infuel tank 11.

The embodiment of FIGS. 5 and 6 is mounted to the same vehicle as in theembodiments of FIGS. 1-4, and like numerals are used to denote thatfact. This embodiment differs from the others in that actuation of theoil supply means is caused by the insertion of the fuel nozzle followingopening of the fill port, rather than as the consequence of manipulatingthe closure of the fill port.

In this embodiment, fuel tank 11 has its top wall formed with aconnecting port 115 and a fuel (or gasoline) supply port 116. Thethreaded lower end of a connector 117 is screwed into theafore-mentioned connecting port 115. The connector 117 is made to have acup shape and is formed with a lower valve port 118 which hascommunication with the fuel tank 11 by way of the connecting port 115.The inside space of the connector 117 forms a communication passagebetween lubricating oil tank 12 and fuel tank 11. In this embodiment,the communication passage also acts as a metering chamber 119 formetering the lubricating oil to be blended, as in the embodiment of FIG.2. A sealing member 120 is screwed into the upper portion of theconnector 117. Into the sealing member 120, there is removably screwedan outlet portion 121 which is formed in the bottom wall of the oil tank12. The sealing member 120 is formed with an upper valve port 122 whichis made coextensive and aligned with lower valve port 118 and which hascommunication with the oil tank 12 by way of the opening of outletportion 121. There is accommodated in the metering chamber 119 a valvemember 123 which is formed with upper and lower valve stems 124a and124b extending therefrom until they are fitted in upper and lower stemguides 125 and 126, respectively, while they freely extend through theupper and lower valve ports 122 and 118. The valve member 123 is sizedand shaped to have its lower side seated removably upon the lower valveport 118 thereby to shut off the valve port 18 but to open the uppervalve port 122 at the same time. Likewise, the upper side of the valvemember 123 can be removably seated upon the upper valve port 122 to shutoff the same while opening the lower valve port 118. The valve member123 thus constructed is always urged downwardly by the biasing action ofa coil spring 127.

An oil level gauge 128 made of a transparent tube or the like iscommunicated at its lower end with the metering chamber 119. This levelgauge 128 is guided upward along the side wall of the oil tank 12 towhere its upper extremity is vented to the atmosphere. Here, referencenumerals 129, 130 and 131 indicate an oil supply port opened in the topwall of the oil tank 12, an oil cap for closing the oil supply port 129,and a sealing member, respectively.

There is provided in the fuel tank 11 a bracket 132 which depends fromthe top wall of the tank 11 and to which an operating lever 134 ishinged by means of a pivot pin 133. The operating lever 134 thusconstructed has one end portion abutting against valve stem 124b, whichdepends from the valve member 123, and its other end extending below thefuel supply port 116 in a manner to face the same. It should be notedhere that the operating lever 134 is formed with a retaining uprightprojection 135 at such a position below the fuel supply port 116 as canretain the end of a fuel supply nozzle, which will be described later inmore detail. On the other hand, the fuel supply port 116 of the fueltank 11 can be opened and closed by means of a fuel cover 136, which isscrewed onto the outer wall of the port 116. Reference numeral 137indicates an air breather which is formed in the fuel cover 136 andvented to the atmosphere.

As best seen in FIG. 6 fuel supply port 116 is so sized as freely toadmit fuel supply nozzle 140 which dispenses fuel from a storage tank ata gas station. When the nozzle 140 is inserted to a preset depth intothe fuel tank 11 through the fuel supply port 116, its leading outlet141 abuts against the end of operating lever 134. Then operating lever134 is turned clockwise by the weight of the nozzle 140. Outlet 141 ofnozzle 140 is so retained by the projection 135 of the operating lever134 that it does not slide off.

Under the normal condition in which fuel cover 136 of fuel tank 11 isclosed, operating lever 134 is released and turned counter-clockwise, asbest seen in FIG. 5. Thus, valve member 123 is pushed down by thebiasing force of coil spring 127. As a result, the lower side of thevalve member 123 is seated to shut off the lower valve port 118 whileopening the upper valve port 122. Then, the inside space of the oil tank12 communicates with metering chamber 119 via the opening of outletportion 121 and upper valve port 122, so that engine oil from oil tank12 flows down into metering chamber 119 and fills it to its fullpredetermined capacity.

When the blended fuel supply runs low, and needs to be replenished, thefollowing operations are carried out. For fuel supply, the vehicle isdriven to a gas station or the like, and fuel supply nozzle 140 isinserted into the fuel tank 11 through fuel supply port 116 afterremoving cover 136 from the tank 11. Then the outlet 141 of nozzle 140abuts against the other end of operating lever 134 so that lever 134 isturned clockwise by the weight of nozzle 140, as shown in FIG. 6. Outlet141 of nozzle 140 is held in engagement with the retaining projection135, and the nozzle 140 is prevented from sliding away from theengagement with operating lever 134, so that the nozzle 140 can maintainits position suitable for the desired automatic fuel supply withoutbeing manually held.

When operating lever 134 is turned clockwise, one end raises valvemember 123 through lower valve stem 124b against the biasing force ofthe coil spring 127. As a result, the lower side of valve member 123 isunseated to open lower valve port 118 and the upper side of the samebecomes seated upon upper valve port 122 thereby to shut off port 122.Then the engine oil which was reserved in metering chamber 119 flowsdown into fuel tank 11 via lower valve port 118 and connecting port 115.Because upper valve port 122 is shut off by means of valve member 123,lubricating oil in the tank 12 cannot flow down into fuel tank 11. Thus,only the preset quantity of the oil which occupied metering chamber 119can be supplied to the fuel tank 11. Because oil level gauge 128communicates with metering chamber 119 and has its upper vented, chamber119 is vented to the atmosphere when the valve member 123 opens thelower valve port 118. Oil in the metering chamber 119 can therefore flowswiftly and smoothly into the fuel tank 11. Only fuel is supplied fromnozzle 140. Fuel flowing into tank 11 establishes vortexes so as to stirand blend into the fuel the oil which has already been supplied. Inthese ways, it is possible to charge into the fuel tank 11 a fuel intowhich a preset proper quantity of oil is blended.

After a preset quantity of oil-blended fuel is supplied up, the nozzle140 is extracted to fasten the cover 136. Operating lever 134 becomesfree from the weight of the nozzle 140. Valve member 123 is moved downby the action of coil spring 127 to open the upper valve port 122 and toclose lower valve port 118. As a result, engine oil is allowed to flowdown from oil tank 12 into metering chamber 119, thus preparing the nextcharge of oil to be supplied to fuel tank 11.

According to the invention, a preset quantity of engine oil can beautomatically supplied to the fuel tank 11. As a result, it issufficient to charge only the fuel into the supply port at a gas stationor the like. Thus, such troublesome operation is not required as hasbeen required in the prior art to blend in advance the oil and fueloutside of the fuel tank before charging them into the tank. Thus, fuelcan be used from stations which do not sell blended fuels. Because theconstruction of the present invention does not require a special pumpfor use in a separate oil supply system, it is considerably simplified,as is the handling, in comparison with the prior art.

Also, oil tank 12 may be made removable, so that instead of refillingthe oil tank a replacement full tank can be substituted for a empty one.Optionally, it may of course merely be refilled through its own fillport.

The quantity of the lubricating oil to be supplied is always at a presetvalue. Therefore the blending ratio between the oil and fuel afteradding the fuel may be different from filling to filling, depending uponthe quantity of oil-blended fuel left in the fuel tank 11 beforerefilling. However, it is possible to maintain the blending ratiosubstantially at a constant level if the fuel level gauge 14 is providedat some position with an indication of some level at which refillingwill result in an optimally proportioned blend.

This invention in its several embodiments frees the user from handlingthe oil or fuel. In all embodiments there is a measuring means, forexample chambers 19 and 119, and cylinder 53 to measure out apredetermined quantity of oil. Actuation means is provided to supply themeasured quantity to the fuel tank. In FIGS. 1-4, the actuation means ispart of the fill port cover (closure), and in FIGS. 5-6, it isresponsive to the filler nozzle. In FIGS. 2 and 5, the oil dischargesinto the fuel tank before the fuel, and so a good blending operation canresult from the turbulent flow of fuel into the tank. In FIG. 4, the oilis injected into the fuel after the fuel is charged into the fuel tank,and this mixing advantage is not provided. However, it enters with somevelocity, which will cause at least some mixing, and the turbulencecaused by motion of the vehicle will later provide sufficient blendingmovement.

This invention thereby provides convenient and clean means for makingblended fuel.

This invention is not to be limited by the embodiments shown in thedrawings and described in the description, which are given by way ofexample and not of limitation, but only in accordance with the scope ofthe appended claims.

We claim:
 1. In combination: a fuel tank having a fill port and aremovable closure for said fill port through which fuel can be charged;an oil tank for containing oil to be blended into fuel contained in saidfuel tank, said oil tank having an inlet port and an outlet portcommunicating with a measuring means, said measuring means comprising achamber of known volume having an inlet opening adapted to receive apredetermined quantity of oil from said oil tank outlet port and anoutlet opening to discharge said predetermined quantity of oil into saidfuel tank; valve means for selectively and alternately closing andopening said inlet and outlet openings; and actuating means foractuating said valve means comprising lever means contactible with saidvalve means, said lever means being so disposed and arranged as to becontacted by a filler nozzle when said filler nozzle is to fill saidtank with fuel, said contact serving to cause said lever means to rotateand to move said valve means to open said outlet opening and close saidinlet opening, said valve means reverting to the condition where theoutlet opening is closed when said contact with said filler nozzle doesnot occur.
 2. A combination according to claim 1 in which said levermeans is a first class lever disposed inside said fuel tank, with onearm engageable with said valve means, and its other arm engageable bysaid filler nozzle when inserted into said fuel tank.
 3. A combinationaccording to claim 2 in which said valve means is biased toward closureof said outlet port.
 4. A combination according to claim 1 in which saidvalve means is biased toward closure of said outlet opening.